The embodiments herein relate generally to firearms and firearm accessories.
FIG. 8 shows rifle R as is known in the art. Rifle R comprises lower receiver L rotationally coupled to upper receiver U at pivot point P. Upper receiver U further comprises protrusion T have protrusion hole H that can be connected to lower receiver L with a locking pin through a plurality of locking pin holes O in lower receiver L. However, this rifle is difficult to clean. Once upper receiver U is rotated away from lower receiver L, it is easy for the two receivers to come back together, pinching the fingers of a human user. Embodiments of the present invention solve this problem.